Test

Getting Started with Test

This tutorial lets you test a Dart application and use Koin inject and retrieve your components.

Setup

First, add the Koin dependency like below:

Package	Pub
koin
koin_test

dependencies:
  koin: ^[laste_version]

dev_dependencies:
  koin_test: ^[laste_version]

Declared dependencies

We reuse the koin dart getting started example, to use the koin module:

final helloModule = Module()
    ..single((s) => HelloMessageData())
    ..single<HelloService>((s) => HelloServiceImpl(s.get()))

Writing our first Test

To make our first test, let's write a simple unit test file and import koin_test.dart. We will be able then, to use by inject() operators.

void main() {
  setUp(() {
    startKoin((app) {
      app.module(helloModule);
    });
  });

  tearDown(() {
    stopKoin();
  });

  var model = get<HelloMessageData>();
  var service = get<HelloService>();

  test('unit test', () {
    var helloApp = HelloApplication();
    helloApp.sayHello();

    expect(service, helloApp.helloService);
    expect("Hey, ${model.message}", service.hello());
  });
}

Mocking

You can use the declare function to declare mocks:

HelloMessageDataMock implements HelloMessageData {}

void main() {
  setUp(() {
    startKoin((app) {
      app.module(helloModule);
    });
  });

  tearDown((){
    stopKoin();
  });

  test('should inject my components', () {

    var dataMock = HelloMessageDataMock();  
    // declare a mock instance to HelloMessageData.
    declare<HelloMessageData>(dataMock);

    // retrieve mock, same as variable above
    expect(get<HelloMessageData>(), isA<HelloMessageDataMock>());

    // then HelloService will be using the mocked instance.
    expect(get<HelloService>().helloMessageData, isA<HelloMessageDataMock>());    
  });
}

Verifying modules

Let's write our check test as follow:

test modules with testModule() function

void main(){
    testModule('moduleChecktest - shoud be a valid module',helloModule);  
}

Getting Started with Test#

Setup#

Declared dependencies#

Writing our first Test#

Mocking#